Problem cropping blog picture (blavatar image)

I removed my existing blog picture (blavatar image) and uploaded a new one.
From here I was taken to the page where you crop the image prior to saving it.
The pre-set cropping lines, square in shape, are smaller than the image I wish to use,
but I can not get the lines to drag to a larger sized box.

I tried re-sizing the image to a smaller size, and then uploaded the smaller image.
The new smaller image appears to be the same size while in the cropping feature,
and I have the same problem as I had with the oriinal image. I can't seem to do anything
with the pre-determined square cropping box other than move the square around on
my image. I could not seem to locate a similar topic while searching the forum.

The size of a blavatars (favicons) when displayed in the address bar or tabs on a browser is 16px x 16px. Try resizing your image down to 32x32 and then do the upload and cropping (or better yet, size it to 16x16 before uploading it.

I tried it at 16 x 16 and 32 x 32 and the same problem exists as originally explained. The cropping feature just gets smaller as the image gets smaller; it still prevents me from retaining the full image within the boundaries of the cropping field.